What functionality is missing? What is unsatisfying with the current situation?

Currently, image carousels can be embedded, but they cannot be resized or aligned like single images can. When a carousel is embedded it is full size, which often looks out of proportion to the surrounding content.  

How does this feature request address the current situation?

Introducing formatting options to carousels would give greater flexibility to how images are displayed in relation the other content in the article.  

What are other uses for this feature request?

None, this is rather a specific feature.